The tribunal heard: “Mr Rahman said he had been told that if he continued to employ the claimant then his customers would cease to patronise him.

“Mr Rahman referred specifically to pressure being placed on him by the head of the Sunni sect who had helped Mr Rahman to gain admission for his daughters to single sex school for girls.”

Mr Rahman claimed he had been influenced by a conference held by KN at the TIC on March 28, where worshippers were ordered to boycott Ahmadi-run shops.

During that conference Mr Gani shared a stage with KN Abdul Rehman Bawa. Mr Bawa said: “I don’t know why our sisters or mothers are talking with these Qadiani and making friendships … I know in this road, Tooting high street, all of the shops who are selling to Qadiani.

“Don’t make friends with them… they are trying to deceive you, they are trying to convert you from Islam to Qadianism.”

The owner of one Tooting halal butchers said his trade had fallen by nearly 50 per cent in three months. He said: “We have lost so much business because some people refuse to come here just because I am Ahmadi. They use words against me like ‘Kafir’, which means I am not Muslim.

“I’ve lived here for 13 years and lots of people know me in Tooting, but this situation has become so much worse now.”

A Wandsworth police spokesman said an investigation into the alleged hate crimes was ongoing.